New Haven — Jurors took less than two hours Wednesday to find Michael Thomas guilty of embezzling from the Mashantucket Pequot Tribe he once led as chairman.

The verdict, which marked the end of a swift, three-day trial, followed closing arguments in which opposing attorneys alternately portrayed Thomas as an arrogant public official and as a caring, generous man entitled to use a tribe-issued American Express card to pay for his dying mother's limousine rides to a dialysis center.

The jury convicted Thomas of one count of theft from an Indian tribal organization and two counts of theft concerning an Indian tribal government receiving federal funds, on each count finding him guilty of embezzlement and willfully or intentionally misapplying funds that belonged to the tribe.

As he headed into a conference room after the verdict was read, Thomas, 45, offered no comment.

"We're very disappointed," said his public defender, Paul Thomas, who is not a relative.

Michael Thomas will remain free on $100,000 bond until his sentencing, which U.S. District Judge Janet Bond Arterton set for Oct. 22. At that time, Thomas will face a maximum prison term of 25 years and a fine of up to $750,000, as well as the forfeiture of $102,393.34 and two personal computers.

For Thomas, the verdict is another chapter in a stunning fall from grace that began with his ouster from the tribal council in August 2009, soon after it came to light that the tribe was in serious financial straits due to declining revenues at Foxwoods Resorts Casino, the western hemisphere's largest casino in terms of gaming.

Thomas, then chairman, pledged to put funding for tribal government and distributions to tribal members ahead of the tribe's obligations to lenders, causing alarm throughout Indian Country and the financial markets.

"Mr. Thomas abused his position as Chairman of the Mashantucket Pequot Trial Nation by charging over $100,000 in unauthorized personal expenses to the Nation," Acting U.S. Attorney Deirdre Daly said in a statement. "These fraudulent expenses continued even after they were discovered and he was told to stop."

Assistant U.S. Attorney Douglas Morabito told jurors during the prosecution's closing argument that Thomas had used a tribe-issued American Express card as "his own personal piggy bank" between October 2007 and September 2009, charging personal expenses in clear violation of a tribal council resolution that limited use of such cards to business purposes.

Testimony during the trial showed Thomas had signed the resolution in 2005. His annual income was more than $860,000 in 2008, but fell to about $354,000 a year later, according to evidence in the trial.

Morabito said Thomas "blatantly, systematically" used funds that belonged to the tribal government for his own benefit, a crime made worse, the prosecutor said, because Thomas occupied a position of trust within the tribe.

American Express statements, invoices and other records the government entered into the evidence of the trial showed Thomas charged nearly $90,000 in connection with his mother's three-times-a-week limousine rides to and from dialysis treatments. He charged another $10,000 for Direct TV and Sirius XM satellite services, two Apple computers and a variety of cellphone and other digital services, the government alleged and the evidence showed.

Paul Thomas, in his closing argument, told jurors the government only could assume the expenses — except for "a handful of small charges" — represented personal expenses. He characterized the case against his client as "guess work," saying the government had failed to achieve its burden of proof.

"What you have here is opinions, belief and assumptions — and that's not proof, let alone proof beyond a reasonable doubt," he said.

Paul Thomas called no witnesses during the trial.

Perhaps telling was the testimony of Michael Thomas' former chief of staff, Jeffrey Wosencroft, who said earlier in the trial that Thomas had told him the charges for limousine rides and Internet and other digital services were personal in nature.

Wosencroft had said he repeatedly told Thomas that he had to stop charging personal expenses to the tribe-issued American Express card.

"Did he stop?" Morabito said. "No. He kept doing it."

Paul Thomas said it was reasonable for Michael Thomas to ensure his mother had transportation to her medical appointments, a service the tribal government often provided to tribal members.

"Wasn't this a service the tribe had to provide?" the defense attorney said.

Thomas' brother Steven, the current tribal treasurer, faces trial on the same three counts of theft in connection with allegations that he accepted payment for time he did not work while employed by the tribal government. The alleged theft occurred before Steven Thomas was elected to the tribal council. Steven Thomas' trial is scheduled for November.